I looked up Cooper and Lovecraft on the web and found two relevant items. The first is from an essay called "Mad Scientists and the Movies" by Douglas Chapman at www.strangemag.com/madscien...entists/madscientists.html The author, discussing Universal Studio's Frankenstein films, quotes from Cooper's screenplay:

The third film in the series, Son of Frankenstein, was made in 1939. The finished film abandons most of the alchemical elements [of previous films] in favor of superscience, but an earlier October 1938 draft of the screenplay has a very interesting reference. Wolf von Frankenstein, the son of Henry, has inherited Castle Frankenstein, which he has not seen since childhood. Visiting its library, he reads off a familiar shelf of his father's books, soon quoting from memory: "Agricola's De Re Metallica ... the Necronomicon ... Roger Bacon ... Euclid ... Paracelsus ... FitzJames O'Brien ... Avicenna! See -- I haven't forgotten!" Not only was scriptwriter Willis Cooper (the original scriptwriter of the Lights Out radio show) aware of the alchemical precursors, but was acquainted with H. P. Lovecraft's Cthulhu mythos as well.

Quiet, Please: "Gem of Purest Ray" (17 May 1948; audio) Written and directed by Willis Cooper (writer of Son of Frankenstein and creator of Lights Out), Quiet, Please was, in the minds of many, the finest—and least appreciated—horror series to appear on old-time-radio. In this episode, it becomes obvious that Cooper had read some Lovecraft, particularly "The Shadow over Innsmouth" (in an episode which aired about two months later, Lovecraft is actually mentioned by name, confirming this suspicion). (30 min.)